Isoelectronic Atoms and Ions

[Samantha Pedersen 2K]

In lecture today, Dr. Lavelle mentioned that isoelectronic atoms and ions have very different properties. I'm wondering why this is the case. If they have the same electron configurations and thus the same number of valence electrons, why do they behave differently?

[Wil Chai 3D]

Regarding his example with with F- and He, I think it's because they both have different nuclear charges. Since He has the same number of protons as electrons, it is neutral. But since F- has one more electron than proton, it has a negative charge and could interact electrostatic-ly with positively charged ions. Hope this helps!

[Crystal Yu 1D]

I think that Professor Lavelle may go over this more in detail in later lectures, but despite having the same number of electrons, ions will have a different number of protons. The proton-electron attraction will affect the size of atomic radius, electronegativity, etc. This may be a reason for the properties being different despite having the same electron configuration.